caffeine - as drugs go, it's relatively safe, cheap, legal, only minimally addictive and chockful of buzz. But what's the healthiest way to mainline it?
Some love their java. Studies indicate that drinking a lot of it may even reduce your risk of diabetes or gallstones. Coffee is even being investigated for a potential ability to stop tooth decay. Overall, though, it's considered to have more negative health effects than positive.
Black tea is lower in caffeine than coffee (50 mg per cup vs 135) and contains some health-promoting compounds that lower heart disease risk. But some experts warn that black tea isn't as nutritious as green. For best results, drink in moderation.
When it comes to the healthiest option, the experts are evenly divided between green tea and South America's yerba maté. Both brews are high in antioxidants that fight cancer and other diseases. Maté has more caffeine, about 50 to 100 mg per cup vs green tea's 30. By the way, anyone who tells you maté contains not caffeine but a wonderful, side-effect-free stimulant called mateine is badly misled or lying. Even worse, some maté beverages are sweetened with asparatame, which some doctors and researchers warn is highly toxic.
Pop scrapes the bottom of the caffeine barrel. Sugar-laden soft drinks screw up your immune system and chase away youth.
Despite its energy-enhancing, mood-elevating charms, caffeine does come with some warnings. For one thing, it stresses the adrenals, feeding long-term exhaustion, and drains minerals from the body, a concern if you're at risk for osteoporosis.
Coffee, tea and yerba maté can also interfere with iron absorption, so it's wise to stay away if you're diagnosed with iron-deficiency anemia. Caffeine avoidance is also prudent if you're super-stressed, have a heart or cardiovascular condition or are pregnant or breastfeeding.
What the Experts Say "My number-one choice is green tea. Its caffeine seems to have the fewest side effects such as insomnia, anxiety and irritability. It also contains an amino acid, theanine, that increases alpha waves in the brain, calming you down and improving the ability to learn and focus. If you're worried about caffeine, get theanine capsules in any health food store and take three with your coffee or whatever; they'll help offset the caffeine's negative effects. The only times I've seen a benefit from coffee is in people with breathing disturbances or asthma. They're actually helped by a little bit of caffeine - no more than two cups a day, and without cream or sugar."
ZOLTAN RONA , MD, MSc
"Maté contains almost twice as many (antioxidant) polyphenols as red wine but does not carry the risk of addiction or wine's high caloric content. Our lab has shown recently that maté extracts are excellent quellers of (cell-damaging substances). In this regard, maté is better than green tea or red wines by a factor of 2 to 3. Maté, tea and coffee cause the same problem when drunk in excess: nervousness and hypersecretion of stomach acid."
ALEJANDRO GUGLIUCCI , MD, PhD, associate professor of biochemistry, Touro University, Vallejo, CA
"The biggest problem with coffee is that it's devastating the soil of the Third World. Tea is not as harmful to the environment. People overstate caffeine's negative properties. It's a memory and performance booster. Unprocessed forms of caffeine behave differently than roasted, processed or synthetic caffeine. Someone with a headache from coffee is unlikely to get one from yerba maté, and the headache caused by the coffee could be taken away by maté. Overall, I think green tea is best. It's got the most antioxidants and relatively low caffeine - Japanese green tea, picked in the springtime instead of the fall, has half the caffeine of other green teas."
ROGER LEWIS , chartered herbalist, Toronto
"Green tea is probably best, because it has other components that counteract caffeine's effects. It's a common misconception that yerba maté doesn't contain caffeine, but it does. Guarana (an Amazonian berry) contains quite a bit of caffeine. It's being used for weight loss and to help with libido. I don't know of any studies that back this up, and I don't recommend it. Pop is the worst. It has half the amount of caffeine you'd find in a coffee, and it's coming with a huge dose of sugar.'
DUGALD SEELY , naturopath, researcher, Canadian College of Naturopathic Medicine, Toronto
"Yerba maté has antioxidant, choleretic (stimulating bile flow from the liver, improving digestion), stimulant and diuretic (increasing urination) properties. Recent studies of test animals show it might decrease cholesterol levels. I consider it a good substitute for coffee and tea because it has the stimulant properties of these drinks plus antioxidant and nutritional properties, due to the vitamins and minerals it contains. Maté is contraindicated in patients with gastric ulcers."
ROSANA FILIP , PhD , faculty of pharmacy and biochemistry, University of Buenos Aires, Argentina